feat(HEL-75): 手机端丝滑度整改①——动效Token/按压反馈/日夜平滑/空态入场

Co-authored-by: multica-agent <github@multica.ai>

app/frontend/m/js/router.js

@@ -144,7 +144,7 @@
   }
 
   function placeholderHtml(title, subtitle) {
-    return '<div class="m-placeholder">' +
+    return '<div class="m-placeholder m-motion-rise-in">' +
       '<span class="m-placeholder-icon">' + icon("inbox", 26) + "</span>" +
       "<h2>" + escapeHtml(title) + "</h2>" +
       "<p>" + escapeHtml(subtitle || "该页面将在后续批次实现，返回即可继续浏览。") + "</p>" +
@@ -172,6 +172,16 @@
       "</div></div>";
   }
 
+  function syncThemeToggleUI() {
+    const dark = document.getElementById("m-app").dataset.theme === "dark";
+    const toggle = document.querySelector("[data-theme-toggle]");
+    if (toggle) toggle.setAttribute("aria-checked", dark ? "true" : "false");
+    const rowIcon = document.querySelector(".m-theme-row-icon");
+    if (rowIcon) rowIcon.innerHTML = icon(dark ? "moon" : "sun");
+    const rowBodySmall = document.querySelector(".m-theme-row-body small");
+    if (rowBodySmall) rowBodySmall.textContent = dark ? "当前：夜间模式" : "当前：日间模式";
+  }
+
   function visibleHubItems(hub) {
     const items = hub && hub.items ? hub.items : [];
     return items.filter(function (item) {
@@ -339,7 +349,7 @@
       const toggle = event.target.closest("[data-theme-toggle]");
       if (!toggle) return;
       global.MobileTheme.toggle();
-      render();
+      syncThemeToggleUI();
     });
     window.addEventListener("hashchange", function () {
       if (internalNav > 0) {